Rotary well drill



Lum 'J. A. ZUBLIN ROTARY WELL DRILL Filed Dec. 27. '1922 2 shawn-Smm 1 l lgvVEToR A BY ATTORNEY www www 1l wm.,

J- A- ZUIBLIN ROTARY WELL DRILL Filed DBC. 2'7. 1922 2 Shmts-Sht 2 INVENTOR M/f XM,

. yATmRA/EY JOHN A. ZUBLIN, OF LOS ANGELES, CALIFORNIA.

ROTARY WELL DRILL.

Application filed December 27, 1922. Serial No. 609,308.

To all whom 'it may concern:

Be it known that I, JOHN A. ZUBLIN, a f

citizen of the Republic of Switzerland, residing at Los Angeles, in the county of Los Angeles and State of California, have invented a new and useful Rotary Well Drill, of which the following is a specification.

This invention relates to rotary well drills, and is particularly directed to improvements in a rotary drill of thegeneral type shown and described in my co-pending application Serial No. 600,840, titled Means for forming a well bore, in which an eccentric noncollapsible rotary underreaming drill is provided and is lowered through a well casing and subsequently rotated to form an enlarged bore below the casing.

An object of the present invention is to provide a drill of the above character which is composed of separable units having a. definite cooperating relation when assembled and adapted to be taken apart fdr the replacement or repair of any of said units.

Another object is to provide a drill having a central pilot bit and an eccentrically disposed reaming member, and in which the pilot bit may be a standard type of rotary well bit, with the reaming member positioned near the upper end of the pilotv bit and adapte-d to engage therewith to maintain said reaming member in a definite position with relation to the pilot bit.

It is a further object to provide a reaming member which is adapted for use with pilot bits of various sizes.

Another object is to provide a holder to be associated with the pilot bit and having a removable reaming cutter positioned in definite relation to the pilot bit.

Another object is to provide a drill including a pilot bit adapted to be secured directly to a drill colla-r, and a reaming member near the upper end of the pilot bit and definitely positioned in relation thereto.

A Jfurther object is to provide a drill in which the reaming member and the pilot bit are separable to permit them to be constructed of different materials and to be separately tempered or otherwise treated.

Various other objects and advanta es will be more fully apparent from the fo lowing description of the aecompanyin drawings which form a part of this disc osure. and which illustrate a preferred form of embodiment of the invention,

Of the drawings:

Figure l is a vertical section through the lower portion of a well bore showing a cemented casing and illustrating the method of lowering or raising the drill through the casing.

Figure 2 is a similar section showing the drill in position for forming an underreamed bore.

Fi ure 3 is a side elevation of the drill and ower end of the drill collar.

Figure 4 is a perspective view of the reaining member.

Figure 5 is an elevation, partly in section, lowing aniodified yform of reaming mem- Figure 6 is a plan section on line 6 6 of Figure 5.

Figure 7 is aview similar to Figure 5. and showing the reaming member of Figure 5 as applied to a pilot bit having a long shank.

Figure 8 is a view similar to Figure 5, showing a furthei-modified form of reaming member.

Figure 9 is a side elevation of Figure 8.

Figure lO is a view showing a reaining member in t-lie form of a holder carrying a removable reaming cutter.

Figure 1l is a plan section of'line 11-11 of Figure 10. I

Figure 12 is a view similar to Figure l0, showing the reaining member of Figure 10 as applied to a pilot bit having a long shank.

A drill oi the general character herein referred to has particular utilityA in the forming an enlarged bore below the lower end of a string of casing, and of a diameter which is greater than the inside diameter of said casing so as to permit the lowering into said enlarged bore, of a second string of casing of the largest size which is capable of being lowered through the lirst casing string.

Heretofore many types of expansible tools have been proposed to accomplish these results, therefore for the purpose of accentuating one ot the distinguishing features of a drill of the character to which this invention refers, attention is directed to the fact that such drill has no parts which expand or collapse and may properly be termed a non-collapsible rotary underreaming drill.

Referring particularly to Figures l to 4 of the drawings, the drill consiets of a pilot bit shown as comprising a fishtail blade l() '65 screwed up tightly on the drill collar.

- which is directly connected to the lower end 1 eing of a combined width permitting the drill to be lowered through a casing below which it is'to be operated.

AS illustrated in Figure 1, the aan is lowered through the casing 5 with its axis, which is indicated by broken line 6, to one side of or out of registry with the axis 7 of the casing.

In this manner it is possible to lower through the casing the non-collapsible drill which has a fixed 'boring radius greater thanv the internal radius of the casing.

By subsequently rotating the-drill there will be created anatural tendency for the drill to automatically center itself with the pilot bit in axial alignment with 'the axis of l the easing so that the roaming blade will effect an enlargement of the pilot bit bore.

When so centered the pilot bit blade 10 will bore a pilot hole in advance of the blade 13 and said blade will function to ream said pilot hole to a diameter larger than the internal diameter of the casing (see Figure 2). One particular advantage of the pilot bit resides in the fact that it serves to positively guide the drill, and thereby prevent side thrust ite which the reaming blade may be subjected, from causing av transverse deflection of the drill.

In the drill shown in Figures 1 to 4 of the drawings, a standard type of ishtail bit is utilize-d as the pilot bit unit, and @the reaming member 12 is in the form of a sleevepo- 'sitioned on a reduced lower portion of the drill collar 11, between the shoulder 14 formed by such reduced portion, and the upper surface 15 of the shank 16 of the fishtail bit. The reaming blade 13 is in this instance formed integral with said sleeve and extends downwardly in front of the blade portion of the fishtail bit to be engaged and driven thereby in a drilling operation. Standard fishtail bits of different widths all are provided with Shanks 16 of uniform diameter and a standard size of tapered pin 17 adapted to be screwed into the lower end of the drill collar, so it will be evident that in the construction shown I may utilize ishtail bits of. various widths, any of which will have an effective cooperation with the reaming member and drill col* lar in fulfilment of lthe purposes of the invention. It may be stated that the length of the reduced. portion of the drill collar in relation to the height-of the sleeve 12 is such as to insure lthe shtail bit being Among the `advantages incident to the above described construction is an interchangeability of parts contributing to a quick and easy replacement of worn or broken parts, and when several lishtail bits ofdilierent widths and several reaming members of different boring radius are available, permitting the selective assembling of these to Jform a drill structure having the proper dimensions for the work to be performed.

Further this detachable unit structure will permit the re'aming member being made of a different material than is the pilot bit,

\for instance the reaming member may be constructed of cast metal such as manganese steelavhile the lishtail bit may be forged l1n the usual manner.

Another .factor which enters largely into the advantages of this improved construction is that of the dressing and tempering or otherwise treating the blades. If the reaming blade and fisht-ail pilot bit were made integral it would bel quite diiicult to temper one blade without drawing the temper from the other, therefore it is very advantageous to provide such a detachable structure as herein shown so that when the reaming blade is made of a forging requiring redressing and tempering, said reaming blade and the fishtail pilot bit may each be separately dressed and tempered, or when the reaming blade be made of cast steel, the pilot bit alone may be separately .dressed and tempered without affecting 4the cast reaming member.

The provision of a cast steel reaining member eliminates the necessity of redressing and tempering the reaming blade in the field and provides an inexpensive member which when worn may be discarded and a new roaming member substituted. This is very desirable from the standpoint of the saving of time in the .field as well as from a manufacturing standpoint, first for the rea son that only a few minutes will be required to replace a worn reaming blade with a new one, and second thevproviding of properly sharpened reaming blades is no't dependent upon the individual ideas of tool l dressers in the field. V

In Figures 5 and 6 there is shown a construction in which the lower inner edge of the reaming blade 13a is longitudinally grooved at 18 and engages upon opposite sides of the fishtail pilot bit.

The construction shown in Figure 7 is similar Ito that shown in Figures 5 and 6, excepting that in this instance the fishtail bit 10a has a shank 16a of sufficient length to entirely support the reaming member so that the drill collar 11a may be of the standard type, without a reduced portion.

Referring to Figures 8 and 9 the reaming member 13b has the lower edge of its sleeve portion notched on diametrically opposite lilo 1,515,819 ail" sides as at 20 to enga-ge the upper edge of the ishtail blade, the reaming blade 13b in this instance being shorter than in the previous described constructions.

In Figures 10 and 11 there is shown a construction in which the shank .16b of the fishtail bit 10b is of the same diameter as the reduced portion of the drill collar and engaging both the shank 16" and the reduced portion of the drill collar 11 is a holder 12b of sleeve form, and which rests upon the surface 15b oi the bit 10b. This holder has an odset portion 21 which has a semi-circular recess 22 extending upwardly from its lower surface and intersecting the bore of.

said holder.

A removable cutter blade 23 has a semicircular shank 24 having its inner surface contoured to lit against the shank 16" of the fshtail bit and the reduced portion of the drill collar. The blade portion of the cutter 23 has its inner surface grooved as at 18b to engage upon opposite edges of the tishtail blade.

1n Figure 12 the shank 16c is of sufli cient length to entirely support the reaming blade holder so that in this instance a standard type of drill collar may be used, and the removable reaming cutter 23a is not grooved to embrace the `fishtail blade but abuts the side of said blade in the same manner as does the blade 13 in Figures 1 to 4.

While the several forms of embodiment herein specifically disclosed are Well adapted to fulfil the objects primarily stated it is to be understood that the invention isnot to be limited in this regard, for it is susceptible of embodiment in various other Jforms, all coming within the scope oi? the following claims.

1 claim:

1. A rotary Well drill comprising a plurality of separable units including a drill collar, a concentric pilot bit, and an intermediate nen-collapsible underreaining unit having an eccentrically disposed cutter element of a boring radius greater than that of the pilot bit and rotatable by enga-gementtherewith.

2. A rotary well drill comprising a plurality of separable units including a drill collar, a concentric pilot bit, and an intermediate nonw-ollapsble iunlerreaniing unit having al cooperating engagenienl with .the bit whereby the hii upon rotation will drive said underrealning unit. said underreaming unit having an eceentrieally disposed cutter element extending laterally beyond the bil.

4. A rotary well drill comprising a collar, a concentric pilot bit detachably secured upon the lower end of said collar, and a non-collapsible underreaming unit mounted between the pilot bit and said drill collar, and having an eccentrically disposed cutter element laterallyextended beyond the bit, a part of said underreaming unit being engageable by said bit to insure a simultaneous rotation of both.

5. A rotary Well drill comprising a drill collar, a concentric pilot bit detachably secured to the lower end of said collar, and a non-collapsible eccentric underreaming member detachably supported at the upper end of the pilot bit and having a driving engagement therewith defining the circular disposition of the underreaming member relative to the pilot bit.

6. A rotary well drill comprising a concentric pilot bit formed for attachment to a drill collar, and a non-collapsible underreaming unit detachably associated with the bit and having an eccentrically disposed cutter element extending laterally beyond the bit, said unit being engageable directly by said bit to insure their simultaneous rotation.

7. A non-collapsible underreaming unit for a rotary well drill comprising a member adapted to be supported in engagement with both a drill collar and a concentric boring bit and having a reaming cutter eccentrically disposed relativeto the axis of the bit. said unit being provided with means for direct engagement by said bit whereby a rotation of the bit will eii'ect a rotation of said unit.

8. A rotary well drill comprising a concentric pilot bit adapted for attachment to a drill collar, and a. non-rcollap/sible underreamer unit including/afholder engaged by both of said members and carryingfr an underreaming cutter rotatable directly by a blade of said pilot bit.` x

Signed at Los Angeles. California. this 20th day of December 1922.

J (l1-1N A. ZUBLIN. 

